Process of volatilizing ores.



S. l. CLAWSON.

PROCESS 0F VOLATILIZING GRESu APPLICATION FILED Ausw. i909.

$22,945@ msnm Apu 9,1918.,

i Y l. S14/newton SELDEN IRWIN CLAWSON, 0F SALT LAKE CITY, UTAH.

PROCESS 0F VOLATILIZING- CRES.

Specification of Letters Patent.

Patented Apr. 9, 1918.

' Application mea Aug-ust 4,1909, serial No. 511,204.

To all whom t may concern.'

Be it known that I, SELDEN I. CLAWsoN, a citizen4 of the United States, residing at Salt Lake City, in the county of Salt Lake, State of Utah, have invented certain new and useful Improvements in Processes of Volatilizing Ores, of which the following is a description, reference being had to the accompanying drawing, and to the letters and figures of reference marked thereon.

The invention relates to a process of treating ores, and more especially the volatilization of roasted ores. While various ores may be treated by my process, it is more especially adapted for use in connection with the reduction of ores containing gold, silver, copper, lead, zinc, antimony or bismuth.

In the extraction of gold, silver, copper and lead from ores by the process of volatilization, it is necessary to heat the ore to a considerable degree. I have found that these volatile metals are much more advantageously caught after the extraction from the gangue, if the volume of air carrying the metal is comparatively small.

The object of this invention, therefore, is to provide a process of extracting the metal from the ore, wherein a comparatively small amount of air carries the metal to the fume arrester. I have found this can be accomplished if the fire gases used in heating the ore to the volatilization point are excluded from the fume arrester.y

The invention consists in preheating or roasting the ore in an oxidizing chamber not of the muiiie type, wherein the fumes and gases are allowed to escape, after which' it is passed in its heated state to a second chamber, where it is again heated and the fumes or gases conveyed to a fume arrester. The ore may be treated with chlorin gas in the volatilizing chamber, or may be treated with a flux, as it is passed from the preheating chamber to the volatilizing chamber. Or the ore may be fluxed before entering the preheating chamber, the gases and air being allowed to escape from said chamber. The

transfer of the ore to the volatilization chamber occurs before the volatilization of the metals takes place.

In carrying out the invention, I prefer to use the herein described apparatus, wherein two furnaces are arranged in tandem, but it will be understood that other arrangements may be used, and that other types of furnaces may be used from those herein described, without departing from the spirit of my invention..

The ligure in the drawing shows more or less diagrammatically and in section an apparatus for carrying out the invention.

The apparatus consists of alfurnace 1, which, as herein shown, is of the ordinary revolving type. The crushed ore is fed to a hopper 2, and from the hopperl 2 by a screw conveyer to the furnace'l. A furnace 3 is located at one end of the furnace 1. Said furnace 3, as lherein shown, consists of a closed chamber having va pipe 4 leading to a fume arrester 5, which may be of any desired type. The fire box 6 located beneath the furnace 3 serves 'as a means for heating the furnace, and the pipe 7 conveys the gases and fumes from the fire box to the furnace 1.

The ore passes through the furnace 1, and is fed into the chute 8, which leads 'to lthe furnace 3. A hopper 9 may be provided with a flux', which is fed by means of the conveyer 10 to the ore, as it passes from the furnace 1 to the furnace 3. A pipe 11 leads into the bottom of the furnace 3, and may be used to convey chlorin gas to the furnace 3. Air may be fed to the pipe 11 through the auxiliary pipe 12, if desired.

'Iheore as it passes from the furnace 1 to the furnace 3, will pile up in the furnace and close the lower en'd of the chute 8, so that the fumes and gases from the furnace 3 will pass through the pipe 4 to the fume arrester. A suitable opening 13 may be formed in the front of the furnace 3, through Which 'the ore in said furnace may be raked and drawn through the opening, when desired. A little air may be fed to the furnace through the opening 13, wheneverl it isfound desirable. Said opening may be closed by any suitable door. In carrying out my improved process, the fire box 6 is charged, and the furnace 3 thoroughly heated. The fumes from the l fire box also pass to the furnace 1, which becomes heated.

The chlorin generator for supplying the chlorin gas and the fume arresterv are, of course, put into shape for operation. rIhe crushed ore is now fed to the hopper 2,

and the ore is then passed by the screw conveyer to a point inside of the furnace 1. The ore travels through the revolving furnace 1j becoming heated more and more un- -til the sulfurous particles in the 'ore-take fire,

' or to a point a little below the point of temperature at which the metal chlorids volatilize. i When the ore reaches the furnace 3, the chlorin gas of the uX which is mixed with the ore as it passes to the furnace, brings about the desired chemical re-action, and the fumes or gases rising from the lore will pass through the pipe 4 to the fume arrester. It will, therefore, be seen that a comparatively small amount of air containing the volatile metals passes through the fumearrester, which greatly increases the efficiency thereof.

lt should be understood that in carrying out mv process, l do not desire to be limited to any particular type of preheating or volatilization furnace. The preheatingfur` nace might consist of a simple roasting furnace of any well known type, and, on the other hand, the volatilization furnace might consist of any revolving muffled lfurnace or a reverberatory furnace, or any other like kind of furnace. v

' rllhe essential features of my invention consist in preheating the ore to a point a few degrees below the point of Volatilization of the metals, the fumes and gases being allowed to escape during "preheating, and then heating the ore to a higher temperature in a substantially closed chamber, and passing the fumes and gases which contain a comparatively small amountl of orefrom said chamber to the fume arrester. .It is understood, of course, that the ore would be c rushed and rabbled, as conditions demand.

Having thus described my invention, what l claim as new and desire t'o secure by Letters Patent, is

The process of treating ores by volatiliza-y tion consisting in subjecting the ore directly to fire box gases for a time for preheating thel same to a temperature below that at which the metal chlorids would volatilize and .allowing the fumes and gases to escape during such preheating, 'treating the heated ore while still hot with a halogen reagent and subsequently volatilizing the halogen compounds out of the ore and passing the products of volatilization to .a fume arrester.

In testimony whereof li atliX my signature, in presence of two witnesses.

SELDEN lRWlN CLAWSON. Witnesses:

WM. T. lEoULGER, W. J. BARNES.l 

